// Storage 封装
const STORAGE_KEY = 'mall';
export default{
    //存储值
    setItem(key,value,module_name){
        if(module_name){
            let val = this.getItem(module_name);
            val[key] = value;
            this.setItem(module_name, val);
        }
        else{
            let val = this.getStorage();
            val[key] = value;
            window.sessionStorage.setItem(STORAGE_KEY, JSON.stringify(val));
        }
    },

    //获取某一个模块下面的属性user下的userName ex: key:mall value:user: {userName: "jack", age: 30, sex: 1}
    getItem(key,module_name){
        if(module_name){
            let val = this.getItem(module_name);
            if(val) return val[key]
        }
        return this.getStorage()[key];
    },

    //获取整个数据
    getStorage(){
        return JSON.parse(window.sessionStorage.getItem(STORAGE_KEY) || '{}');
    },

    //清空某一个值
    clear(key, module_name){
        let val = this.getStorage();
        if(module_name){
            delete val[module_name][key];
        }else{
            delete val[key];
        }
        this.setItem(STORAGE_KEY,val);
    }
}